This invention relates to improvements in nasopharyngeal airways which maintain the airway in a secure position so that oxygen may be reliably delivered to a patient and secretions may be removed without disturbing the position of the airway.
Prior art nasopharyngeal airways usually consist of a tubular airway which can be inserted through a nostril of a patient with the purpose of creating a passageway to the throat to ensure that the patient has a consistently open breathing passage or airway. Depending on a patient""s age, size, and anatomy, an effective airway may range from 4 inches to 6 inches long from the nares or nasal opening to the nasopharynx region. Semi-rigid, smooth, somewhat soft and pliable synthetic or natural rubber-like materials are generally used in constructing such airways. In a typically airway, a flange at the nasal end is used to hold the airway in place relative to the nasal passage.
Nasal airways find use during surgery or during other periods when it is vital that there will be an open breathing passage and the risk of collapse or obstruction must be obviated. Also, in periods of emergency or intensive care it is desirable that the airway be large enough to allow the introduction of a smaller tube through the airway for feeding, removing secretions, or treatments, or for insertion of a probe for observation.
Thus, it is a general object of the present invention to provide a nasal passageway which will remain in position when used in the foregoing described manner.
The continued and positive introduction and supply of oxygen to a patient is of utmost importance. In some prior art nasopharyngeal or transnasal airways an oxygen supply tube is run along the outside of the airway tube or through the interior of the tube. In both instances, the presence of an additional tube introduces unnecessary complications and also creates the risk that the additional tubing may be collapsed during other procedures performed through the airway. Accordingly, it is another object of the present invention to provide an airway which will protect the integrity of the oxygen supply to the patient.
One prior art nasopharyngeal airway is described in U.S. Pat. No. 4,821,715 which issued on Apr. 18, 1989 to Michael V. Downing. In the Downing patent an oxygen delivery lumen is provided within the wall of the airway tube but part of the lumen projects into the airway passageway and can be subject to being pinched or punctured or collapsed. Accordingly, it is still a further object of the present invention to provide an oxygen delivery lumen within a transnasal passageway which is protected from being collapsed or ruptured.
Also, in the above mentioned Downing airway there is no way to lock or secure the airway in place. When a probe or secretion removal nozzle is inserted, if there is any friction or rubbing or wedging, such probe or nozzle may also withdraw the airway as it is removed. Thus, it is a primary object of the present invention to provide a means and method for preventing the unwanted and premature withdrawal of an airway from a patient.
Other prior art transnasal passageways are shown and described in, for example, U.S. Pat. No. 5,664,567 which issued on Sep. 9, 1997 to Gerald S. Linder and in U.S. Pat. No. 5,692,506 which issued on Dec. 2, 1997 also to Gerald S. Linder. In the last mentioned patent, a transnasal passageway is shown which allows the introduction of a probe through the airway to monitor the results of certain surgical procedures. To hold the probe in place a thumb screw device is used. Still, when withdrawing the probe after release of the screw the possibility of either having to withdraw the airway completely and reinsert another is presented which adds to patient discomfort; and, also, to the likelihood that with each insertion and removal trauma can be introduced into surrounding nasal passage tissues. Thus, it is still another object of the present invention to provide a transnasal passageway which can be locked into place and remain for an extended period of time while providing oxygen and an open passageway for removal of secretions or introduction and removal of diagnostic probes.
The foregoing and other beneficial objects of the present invention will be apparent once the following Summary of the Invention, Drawings, and Detailed Descriptions are read and understood by those skilled in the art.
In one aspect the present invention is an improvement in nasopharyngeal or transnasal airways which comprises an inflatable cuff surrounding the airway adjacent the distal or interior end of the airway that can be inflated once it is inserted and positioned in the nasal passage of a patient so that the airway will be secured in place when the cuff is inflated.
In another aspect, the present invention is an improved nasopharyngeal airway for controlling drainage of naturally secreted fluids and for supplying oxygen to a patient who is either conscious or unconscious comprising a tube having sufficient rigidity so that lumens and ducts formed in its walls will not readily collapse, the tube having an open central passageway from end to end; a flange at one end of said tube, said flange being of sufficient diameter to prevent further insertion at the patient""s nares; an inflatable cuff associated with the other or distal end of said tube; and, means for inflating the cuff when said tube has been inserted into the nasopharyngeal passageway of a patient up to said flange whereby when inflated said cuff and said flange operate to hold the tube securely in place. The tube may be provided with an extension which has ports for oxygen and for air. The oxygen port connects with a lumen that extends the length of the extension and the length of the tube and is formed integrally within the wall of the tube without creating a projection on the interior wall of the tube. The oxygen lumen terminates at the distal end of the tube in an orifice which is open to the patient""s breathing passageways. The air port formed on the tube extension connects with an air duct which is preferably integrally formed in the tube extension and is coaxial with the wall of the tubing and is formed therein so that the duct does not form any projection into the central passageway of the airway. This duct continues to a point adjacent the distal end of the tube where it terminates in an orifice which opens on the outer surface of the tube. An inflatable membrane is attached over the opening at this point and is sealed to the outer surface of the tube around the opening. This membrane may be in the form of a sleeve made of hypo-allergenic rubber-like or thermoplastic materials. The requirements are that the membrane be flexible and air impervious and sealable to the tubing material. Such materials are well known to those skilled in the art. An air supply or syringe pump means is provided at the other or proximal end of the airway. The air supply means preferably comprises a syringe and one way valve that can inject just the small amount of air required to inflate the cuff, preferably about 3 cc to 8 cc.
In yet another aspect, the present invention is an improved method for providing continuous oxygenation and an open airway for a patient in a conscious or unconscious state comprising of the steps of providing a nasopharyngeal airway having an inflatable, locking cuff adjacent one end thereof, a nares contacting flange adjacent the other end of said airway; providing an oxygen supply lumen connecting to an opening at the locking cuff end of said airway, said lumen being coaxial with said airway to deliver oxygen at said opening; inserting said airway into a patient""s nasal passageway to a position where said cuff is located in the posterior portion of the patient""s nasopharynx; and, inflating said cuff to contact the wall of said nasopharynx to securely lock said airway so that subsequent patient movement, oxygenation or removal of secretions through said airway will not dislodge the position of said airway. For further understanding and appreciation of the invention and its advantages reference is made to the Drawings and Detailed Description below.